Refactor CacheLayer to improve Redis instance management by returning null if caching is disabled and handling connection errors more gracefully.

src/Socialbox/Classes/CacheLayer.php

@@ -2,15 +2,50 @@
 
     namespace Socialbox\Classes;
     
+    use Exception;
+    use Redis;
+
     class CacheLayer
     {
-        private static CacheLayer $instance;
+        private static ?Redis $instance = null;
 
-        public static function getInstance(): CacheLayer
+        /**
+         * Get the Redis instance, returns null if caching is turned off or there was an error connecting
+         * to the Redis server.
+         *
+         * @return Redis|null
+         */
+        public static function getInstance(): ?Redis
         {
-            if (!isset(self::$instance))
+            // Return null if caching is turned off
+            if(!Configuration::getCacheConfiguration()->isEnabled())
             {
-                self::$instance = new CacheLayer();
+                return null;
+            }
+
+            if (self::$instance === null)
+            {
+                try
+                {
+                    self::$instance = new Redis();
+                    self::$instance->connect(
+                        Configuration::getCacheConfiguration()->getHost(),
+                        Configuration::getCacheConfiguration()->getPort()
+                    );
+
+                    if(Configuration::getCacheConfiguration()->getPassword() !== null)
+                    {
+                        self::$instance->auth(Configuration::getCacheConfiguration()->getPassword());
+                    }
+
+                    self::$instance->select(Configuration::getCacheConfiguration()->getDatabase());
+                }
+                catch (Exception $e)
+                {
+                    self::$instance = null;
+                    Logger::getLogger()->critical($e->getMessage(), $e);
+                    return null;
+                }
             }
 
             return self::$instance;